China’s space technology was deeply applied in the country’s various industries in 2022, forming an all-weather remote sensing monitoring system for infrastructure including all sea areas and islands under its jurisdiction, the China Aerospace Science and Technology Corporation (CASC) said on Wednesday during the release of the Blue Book of China Aerospace Science and Technology Activities. 

China has developed a series of satellites for ocean color, marine dynamics and surveillance, which have formed the capability of continuously and frequently covering observations of global waters, and have achieved remarkable results in applications in areas including island management, marine resource investigation and supervision, marine environmental monitoring and forecasting.

In 2022, China's marine satellites continued to carry out remote sensing inspections of key islands and reefs. In particular, they strengthened monitoring of the waters around Huangyan Island, Diaoyu Island and all the islands of Xisha, Zhongsha and Nansha Islands, providing important data support for the management of sea areas and comprehensive management of the islands.

China's marine satellites also continued to carry out remote sensing detection of key islands and reefs in 2022, in particular strengthening the monitoring of the waters around Huangyan Island, Diaoyu Island, as well as the Xisha, Zhongsha and Nansha Islands, providing a significant basis for the utilization of waters and coastal islands, the report noted.

In addition, China’s marine satellites are also carrying out global ocean observation and forecasting, providing services for global marine dynamic environment monitoring, marine forecasting and disaster monitoring, as well as remote sensing monitoring of global sea level changes.

China's marine satellites have successfully provided important data and technical support for monitoring and warnings for fires, typhoons and storm surges at home and abroad.

Lin Mingsen, director of the National Satellite Ocean Application Service, said China will further strengthen the integration of artificial intelligence, big data and other technologies with satellite remote sensing systems, so as to provide high-quality marine satellite public service products and promote the level of marine management in China.

South China’s Shenzhen vowed on Wednesday to intensify its crackdown on ill-intentioned speculation and smears against private businesses among its newly 20-point measures to boost the private economy, according to Shenzhen Fabu, the official WeChat account of the Shenzhen Government Information Office.

The move marks a prompt response from local authorities to implement the comprehensive guidelines recently issued by the central government to support the private sector.

According to the measures, Shenzhen will step up efforts to combat deliberate speculation, rumors, and defamation against private enterprises and entrepreneurs. The city will also crack down on "online blackmouths" in accordance with the law to create a favorable social atmosphere that respects and supports the growth of private entrepreneurs.

The city will also actively promote leading private enterprises in emerging fields such as new energy vehicles, artificial intelligence, and new energy storage. Moreover, it will foster national and provincial-level characteristic industrial clusters for small and medium-sized enterprises.

To strengthen financing support for private enterprises, Shenzhen will establish a 5 billion yuan ($685 million) fund to hedge risks in loans to small and micro enterprises and reduce the guarantee fee rate for financing these enterprises by government financing institutions to below 1 percent.

Efforts will also be made to support private companies in expanding the overseas market and participating in overseas projects brought by opportunities from the Belt and Road Initiatives and the Regional Comprehensive Economic Partnership.

Shenzhen is home to a long list of renowned private firms such as Huawei, Tencent, and BYD. Its private sector has been one of the most dynamic in major Chinese cities, playing an outsized role in the city’s economy, according to Shenzhen Daily.

By the end of 2022, there were 2.379 million private companies in Shenzhen, accounting for 97 percent of the city’s overall firms. The private economy comprised 55.9 percent of the city’s GDP, according to the report.

SALT LAKE CITY — When black holes collide, astronomers expect to record a gravitational wave “chirp.” But rapidly spinning black holes, like the one featured in the 2014 film Interstellar, might prefer singing to chirping.

According to the calculations of Caltech physicist Kip Thorne, who served as scientific consultant for Interstellar, the movie’s black hole, known as Gargantua, must have had a mass 100 million times that of the sun and whirled about its own axis at breakneck speeds. These characteristics would explain the extreme time dilation on the world where the film’s intrepid planet hunters landed: In one hour there, seven elapsed on Earth, a phenomenon predicted by Einstein’s general theory of relativity.
If a rapidly spinning black hole merges with a companion, it would produce a unique signal — one that gravitational wave detectors might be able to observe, physicist Niels Warburton of MIT reported April 18 at a meeting of the American Physical Society. “There is a completely different gravitational wave signature,” said Warburton, who coauthored a related paper posted online at arXiv.org on March 3.

The standard signal of merging black holes is a “chirp,” named for the increase in frequency and amplitude of the gravitational waves produced as the black holes spiral inward. When converted into sound waves, this pattern sounds like a bird’s chirp. Warburton and colleagues performed calculations to determine the gravitational wave signature from a merger with a black hole spinning at nearly full tilt. Instead of a chirp, they found the gravitational waves would instead maintain a constant pitch, but slowly fade away.

“It was certainly very unexpected to see something that didn’t chirp,” says physicist Jolyon Bloomfield of MIT, who was not involved with the research. “This is really quite interesting work. It shows that the chirp actually goes away — something else is happening here.”

If such black hole mergers occur in nature, next-generation gravitational wave observatories like the Evolved Laser Interferometer Space Antenna might provide proof of their existence. Plans call for eLISA to measure gravitational waves from space beginning in 2034. “These are definitely detectable with eLISA,” Warburton said.

The Advanced Laser Interferometer Gravitational-Wave Observatory, which made the first detection of gravitational waves in 2015 (SN: 3/5/16, p. 6), might be able to observe such mergers if the conditions were just right. Although LIGO can’t observe the mergers of black holes as massive as Gargantua, smaller spinning black holes would produce a similar effect.
Finding black holes like Gargantua would have an impact beyond Hollywood. Spinning black holes are “really interesting from a fundamental physics point of view,” says Samuel Gralla of the University of Arizona in Tucson, a coauthor on the new paper.

Black holes can spin up faster and faster as they suck in matter, but scientists think there’s a limit to how fast they can go. At the center of a black hole is a singularity, or region of infinite density, which is hidden by an event horizon — the surface beyond which nothing can escape the black hole’s greedy pull. But if the black hole twirls too fast, the singularity becomes exposed. Such a “naked singularity,” as it is known, is thought to be impossible to reach, because the known laws of physics would break down.

According to the scientists’ calculations, black hole mergers sing when the larger black hole is rotating just below the limit, at 99.99 percent of its maximum speed. This makes singing black holes an enticing prospect for understanding physics at its extremes.

A newly discovered species of tomato belongs in a haunted house, not on a sandwich.

Fruit from the bush tomato plant Solanum ossicruentum bears little resemblance to its cultivated cousins. The Australian tomato, about a couple centimeters wide, grows enclosed in a shell of spikes. These burrs probably help the fruit latch on to the fur of passing mammals, which then spread the tomato’s seeds elsewhere, researchers at Bucknell University in Lewisburg, Pa., report May 3 in PhytoKeys.

Slice open the fearsome fruit and within five minutes, its sticky white-green flesh appears to bleed, flushing bright red to dark maroon in response to air exposure. One brave researcher tasted an unripe fruit and deemed it salty. The bush tomato becomes no more appetizing with time: Mature fruits harden into dry, bony nuggets.

The tomato’s gruesome qualities inspired its name, courtesy of a group of Pennsylvanian seventh-grade science students: “Ossicruentum” combines the Latin words for “bone” and “bloody.”

Social media supporters of the Islamic State, or ISIS, form online groups that may provide clues crucial to predicting when terrorist attacks will take place, a new analysis finds.

These virtual communities drive ISIS activity on a Facebook-like site called VKontakte, say physicist Neil Johnson of the University of Miami in Coral Gables, Fla., and colleagues. VKontakte, a social networking service based in Russia with more than 350 million users, allows messaging in many languages and is used worldwide.
In the June 17 Science, Johnson’s team describes a mathematical model that predicts online groups of ISIS supporters will proliferate days before real-world Islamic State attacks. That’s just what happened in September 2014, researchers say. Pro-ISIS groups on VKontakte mushroomed the day before Islamic State forces overran Kobane, a small Syrian town.

The researchers refer to groups of followers of an online page that form spontaneously as aggregates. “Our work suggests that, to manage and monitor online ISIS activity, we need to focus on aggregates rather than individuals,” Johnson says.

Pro-ISIS aggregates on VKontakte exchanged information on issues such as recruiting fighters to Syria and how to survive drone attacks.

The new model suggests that authorities need to shut down online pro-ISIS groups in their early stages. Small-scale aggregates favoring the same cause gradually expand when left alone and eventually merge into a much larger online community that’s more difficult to break up, Johnson’s model forecasts.

“This is the first serious, large-scale, data-driven study that shows how online support develops for terrorist groups such as ISIS,” says computer scientist V.S. Subrahmanian of the University of Maryland in College Park, who builds computational models of terror networks. But it remains to be seen whether the new model can predict when and possibly where future Islamic State attacks will occur, Subrahmanian cautions.
Johnson’s team identified 196 pro-ISIS aggregates, consisting of 108,086 individual followers, which operated between January 1 and August 31, 2015. Intelligence agencies, hackers and website moderators work to shut down these online groups, but to a lesser extent on VKontakte than on Facebook.

Pro-ISIS aggregates rapidly adapted to these survival threats in several ways, the researchers say. Fifteen percent of aggregates changed their online names; 7 percent flipped back and forth between opening their content to any VKontakte user or to current aggregate followers only; and 4 percent engaged in a digital form of reincarnation. Pro-ISIS aggregates under unusually intense attack by hackers and others opted for reincarnation, Johnson says.

Reincarnating aggregates disappeared and then returned, often within weeks, with new names and at least 60 percent of the same followers as before. Aggregates that vanished appear to have reassembled without any direction or urging from one or a few members, Johnson says. New names of reincarnated groups often resembled original names enough to alert former members but not enough to trigger VKontakte’s automated system for identifying names of probable pro-militant groups, he points out.

As with predictions of terror attacks based on the expansion of pro-ISIS aggregates, the new model shows promise in predicting when mass public protests will occur based on sudden jumps in numbers of pro-protest aggregates, the scientists say. There is a difference: Reincarnation did not appear within the last three years among Facebook aggregates consisting of civil protesters in Brazil and several other Latin American countries, the researchers found. Those online groups experienced fewer pressures to shut down than pro-ISIS aggregates on VKontakte did.

Johnson’s analysis moves the study of online militant groups forward, says terrorism analyst J.M. Berger of George Washington University in Washington, D.C. But it’s likely that considerably fewer members of pro-ISIS aggregates than the total studied in the new analysis were actually hard-core Islamic State supporters, Berger contends. Concerted efforts to shut down online terrorist networks have depressed numbers of committed ISIS supporters using social media, in his view. Berger and a colleague have found that English-language Twitter use has declined sharply among ISIS supporters over the last two years, due to suspensions of their accounts by the social media site.

Johnson suspects most pro-ISIS aggregate members were staunch supporters, since aggregates aggressively weed out those deemed unserious or hostile.

Terrorists use chains of social and messaging sites online to achieve their ends, Subrahmanian says. How that works, and whether the same aggregate operates under different guises from one site to the next, has yet to be studied.